From 48d1e4711a337819a3fe1c4b22f74ed5495eb768 Mon Sep 17 00:00:00 2001
From: kettenis <kettenis@openbsd.org>
Date: Mon, 21 Feb 2022 19:15:58 +0000
Subject: [PATCH] Convert KVA allocation to km_alloc(9).

ok mpi@
---
 sys/arch/arm/arm/pmap7.c      |  7 ++++---
 sys/arch/arm/arm/vm_machdep.c | 34 ++++++++++++++++++----------------
 2 files changed, 22 insertions(+), 19 deletions(-)

diff --git a/sys/arch/arm/arm/pmap7.c b/sys/arch/arm/arm/pmap7.c
index ffad79e0b5e..c8844b51d09 100644
--- a/sys/arch/arm/arm/pmap7.c
+++ b/sys/arch/arm/arm/pmap7.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pmap7.c,v 1.62 2022/02/01 19:57:28 kettenis Exp $	*/
+/*	$OpenBSD: pmap7.c,v 1.63 2022/02/21 19:15:58 kettenis Exp $	*/
 /*	$NetBSD: pmap.c,v 1.147 2004/01/18 13:03:50 scw Exp $	*/
 
 /*
@@ -625,7 +625,8 @@ printf("%s: %d\n", __func__, ++nl1);
 
 	/* Allocate a L1 page table */
 	for (;;) {
-		va = uvm_km_valloc(kernel_map, L1_TABLE_SIZE);
+		va = (vaddr_t)km_alloc(L1_TABLE_SIZE, &kv_any, &kp_none,
+		    &kd_nowait);
 		if (va != 0)
 			break;
 		uvm_wait("alloc_l1_va");
@@ -686,7 +687,7 @@ pmap_free_l1(pmap_t pm)
 	uvm_pglistfree(&mlist);
 
 	/* free backing va */
-	uvm_km_free(kernel_map, (vaddr_t)l1->l1_kva, L1_TABLE_SIZE);
+	km_free(l1->l1_kva, L1_TABLE_SIZE, &kv_any, &kp_none);
 
 	free(l1, M_VMPMAP, 0);
 }
diff --git a/sys/arch/arm/arm/vm_machdep.c b/sys/arch/arm/arm/vm_machdep.c
index 7ae64366c3c..75e19c2d64a 100644
--- a/sys/arch/arm/arm/vm_machdep.c
+++ b/sys/arch/arm/arm/vm_machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vm_machdep.c,v 1.27 2021/05/16 06:20:28 jsg Exp $	*/
+/*	$OpenBSD: vm_machdep.c,v 1.28 2022/02/21 19:15:58 kettenis Exp $	*/
 /*	$NetBSD: vm_machdep.c,v 1.31 2004/01/04 11:33:29 jdolecek Exp $	*/
 
 /*
@@ -135,6 +135,11 @@ cpu_exit(struct proc *p)
 	sched_exit(p);
 }
 
+struct kmem_va_mode kv_physwait = {
+	.kv_map = &phys_map,
+	.kv_wait = 1,
+};
+
 /*
  * Map a user I/O request into kernel virtual address space.
  * Note: the pages are already locked by uvm_vslock(), so we
@@ -146,26 +151,29 @@ vmapbuf(struct buf *bp, vsize_t len)
 	vaddr_t faddr, taddr, off;
 	paddr_t fpa;
 
-
 	if ((bp->b_flags & B_PHYS) == 0)
 		panic("vmapbuf");
-
 	faddr = trunc_page((vaddr_t)(bp->b_saveaddr = bp->b_data));
 	off = (vaddr_t)bp->b_data - faddr;
 	len = round_page(off + len);
-	taddr = uvm_km_valloc_wait(phys_map, len);
+	taddr = (vaddr_t)km_alloc(len, &kv_physwait, &kp_none, &kd_waitok);
 	bp->b_data = (caddr_t)(taddr + off);
-
 	/*
 	 * The region is locked, so we expect that pmap_pte() will return
 	 * non-NULL.
+	 * XXX: unwise to expect this in a multithreaded environment.
+	 * anything can happen to a pmap between the time we lock a
+	 * region, release the pmap lock, and then relock it for
+	 * the pmap_extract().
+	 *
+	 * no need to flush TLB since we expect nothing to be mapped
+	 * where we we just allocated (TLB will be flushed when our
+	 * mapping is removed).
 	 */
 	while (len) {
 		(void) pmap_extract(vm_map_pmap(&bp->b_proc->p_vmspace->vm_map),
 		    faddr, &fpa);
-		pmap_enter(pmap_kernel(), taddr, fpa,
-		    PROT_READ | PROT_WRITE,
-		    PROT_READ | PROT_WRITE | PMAP_WIRED);
+		pmap_kenter_pa(taddr, fpa, PROT_READ | PROT_WRITE);
 		faddr += PAGE_SIZE;
 		taddr += PAGE_SIZE;
 		len -= PAGE_SIZE;
@@ -183,18 +191,12 @@ vunmapbuf(struct buf *bp, vsize_t len)
 
 	if ((bp->b_flags & B_PHYS) == 0)
 		panic("vunmapbuf");
-
-	/*
-	 * Make sure the cache does not have dirty data for the
-	 * pages we had mapped.
-	 */
 	addr = trunc_page((vaddr_t)bp->b_data);
 	off = (vaddr_t)bp->b_data - addr;
 	len = round_page(off + len);
-	
-	pmap_remove(pmap_kernel(), addr, addr + len);
+	pmap_kremove(addr, len);
 	pmap_update(pmap_kernel());
-	uvm_km_free_wakeup(phys_map, addr, len);
+	km_free((void *)addr, len, &kv_physwait, &kp_none);
 	bp->b_data = bp->b_saveaddr;
 	bp->b_saveaddr = NULL;
 }
-- 
2.20.1